Bait grinder

ABSTRACT

It is provided a bait grinder ( 10 ) adapted for cutting bait fish into chum bait and for grinding it, comprising an oblong housing ( 11 ) for feeding by gravity the bait fish; cutting means ( 30 ) fastened to lower end of an axial shaft ( 31 ); filtering means ( 33 ) at the housing outlet cooperating with means for keeping the filtering function thereof, wherein the cutting ( 30 ) comprise scything cutting mean ( 35 ) which are also means for driving and comprising the chum bait against the filtering mean ( 33 ) for grinding them—and shearing cutting means ( 36 ) for cutting residual chum bait retained by the filtering means ( 33 ) for cutting residual chum bait retained by the filtering means ( 33 ), which are in sliding contact with these latter.

FIELD OF THE INVENTION

The present invention relates to a device for cutting up chunks of baitfish—such as sardine or herring—, commonly termed chum, and for grindingup such chum. Such a device, which will be termed bait grinder, isintended to the baiting of fish having a relatively small size, such aspimps or little tunas. It is also intended to be used in cooperationwith, or in place of, the chum dispenser disclosed in the patentapplication WO 98/58539 and intended to the amateurish baiting of bigfish, such as giant tuna, shark and swordfish, known as big game andcarried out according to a technique termed drifting, consisting inletting the craft used for fishing go adrift under the action of windand sea currents.

BACKGROUND ART

U.S. Pat. No. 5,205,778 discloses a bait chummer whose cutting meansconsist of a plurality of spaced apart circular saw blades mounted on arotatable shaft, which is intended to be manually driven by means of ahand crank and arranged within the central duct of a housing intended tofeed the cutting means by gravity.

U.S. Pat. No. 3,249,257 discloses a bait chummer whose cutting meansconsists of a knife in the form of a reciprocating piston intended toact on the fish contained in a chute having a wall synchronicallymovable with the piston, which is perpendicular to the axis of such achute, at the level of an outlet of this latter.

BRIEF DESCRIPTION OF THE INVENTION

The present invention seeks to provide an improvement for such anamateurish fishing by providing a bait grinder as specified in claim 1attached to this disclosure. Other features of such a device arespecified in the claims dependent on claim 1 and also attached to thisdisclosure.

An advantage which may be obtainable with the present invention isavoiding to mess the craft and the fisher's hands as well, whileensuring a relatively high operation range and a relatively lowenergetic consumption.

BEST MODE OF CARRYING OUT THE INVENTION

A preferred embodiment of the present invention is disclosed below, byway of example only, with reference to the following figures attached tothis disclosure and synthetically summed up hereinafter:

FIG. 1 is a perspective view of a preferred embodiment of the invention;

FIG. 2 is an exploded view of the device shown in FIG. 1;

FIG. 3a, FIG. 3b and FIG. 3c are views, respectively, of the doubleblade cutting helix, of the counter-blade and of the centring stirrup ofthe driving shaft of the device according to the invention, each itembeing shown developped in a plan before being shaped;

FIG. 4a and FIG. 4b are two alternative embodiment of the pierced diskintended to cooperate with the double blade cutting helix and thecounter-blade shown developped in a plan in FIG. 3a and in FIG 3 b,whereas FIG. 4c shows the double blade cutting helix shown in a plan andmounted on the alternative embodiment of the pierced disk correspondingto FIG. 4a, the portion of such a disk below the double blade cuttinghelix being seen showing through;

FIG. 5a is a plan view of the shaped embodiment of the double bladecutting helix, whereas FIG. 5b and FIG. 5c are perspective views of suchan helix and FIG. 5d is a front view of the same;

FIG. 6a is a front view, whereas FIG. 6b and FIG. 6c are a bottom and atop perspective view, of the double blade cutting helix, of thecounter-blade and of the pierced disk shown mounted together on thelower end of the shaft of the bait grinder.

The device 10 according to the invention (see FIG. 1 and FIG. 2)comprises an oblong housing 11 consisting of a cylinder having avertical axis with an inlet 12 at the top end thereof, through whichbait fish (not shown, but consisting of sardines, herrings, pimps orother species), are fed and an outlet 13 at the bottom end thereof, fromwhich the fed fish get out grinded by the means according to theinvention which will be disclosed hereinafter.

Fastening means 20 allow the anchoring of the housing 11 to a craft (notshown), while letting this latter lean above the sea water. Suchfastening means comprise an L-shaped stirrup 21, whose vertical wing 22is intended to be fastened to the wall of the cylinder 11 by means ofscrews 23 and the corresponding nuts, whereas the horizontal wing 25 isintended to be fastened, by means of a screw 26 having a head shaped asa manoeuvring knob 27, to a fastening device 28: this latter is intendedto compensate the possible slope of a support basis of the craft andcomprises two superimposable pieces 28 a and 28 b, which get in contactwith one another through a sloping surface and can rotate one inrelation to the other in order to ensure the fastening of the housing toany type of craft in a substantially vertical position; the fastening tothe craft is obtained by means of screws 29 intended to be covered bythe horizontal wing 25.

The cutting means 30 (see also FIG. 6a, FIG. 6b and FIG. 6c) arearranged at the lower end of a shaft 31 intended to occupy the centralposition of the axis of the housing 11. Such cutting means, which willbe disclosed in detail hereinafter, are thus intended to be driven bythe rotation of the shaft 31. To that effect, it is provided an electricdriving motor 40 equipped with a speed reducer 40 a: for example, a lowpower motor of 5 watts having a speed variable with continuity up to 20revolutions per minute; such a motor is protected by a housing 41 madefrom plastic material and comprising a basis 42 and a cover 43. Ofcourse, the basis 42 is pierced so as to allow the fastening of themotor 40 thereto as well as the crossing of the driving shaft 44therethrough (a seal 45 ensures the watertightness), the connectionbetween the driving shaft 44 and the driven shaft 31 being ensured by akeying spline 31 d; the cover 43 is pierced so as to allow thepositioning, on the top thereof, of the switch 46 and knob 47 for thespeed variation (of course, the base 42 and the cover 43 of the motorhousing 41 can be fastened to each other by means of screws 48). Themotor housing 41 is also intended to protect the electronic circuit 49,whose design is standard and which controls the motor 40. In order tomake easy, on the one hand, the feeding of the bait fish into the fishhousing 11 and, on the other hand, the upholdingin its position of themotor housing 41, the upper portion of the cylinder 11 is equipped witha mouthpiece 14 having a bell-shaped rim and being intended to befastened to the cylinder 11 by means of screws 15. Such a mothpiece 14is also intended to receive a stirrup 16 for centring the driven shaft44 (see also FIG. 3c): to that effect, the stirrup 16 is mediallyprovided with a hole 17 for the crossing of the driving shaft 44,whereas laterally it is provided with holes 19 for fastening it by meansof screws to the bell-shaped rim of the mouthpiece 14; furthermore, thismouthpiece has a buttonhole 18 for supporting the motor housing 41 andavoiding its rotation with the driving shaft 44. The shape of thestirrup 16 can be better appreciated by looking at FIG. 2, which showsit in prospect, and at FIG. 3c which shows it developped in a planbefore shaping it the two wings 16 a and 16 b are intended to be foldedupwards and slightly outwards so as to fit the bell-shaped rim of themouthpiece 14.

The cutting means 30 comprise a metal helix 32 having a special shape(see also FIG. 5a to FIG. 5d, a pierced metal disk 33, which is intendedto close the outlet of the fish housing 11 and along whose inner faceslides the helix 32, and a counter-blade 34 intended to slide along theouter face of the disk 33. The helix 32 is a double blade cutting helixcomprising two diametrically opposed blades 35 and 36, whose developmentin a plan (see FIG. 3a) allows to appreciate that the shape of theleading edges 35 a and 36 a is semicircular, with the centres in 35 cand 36 c respectively (the plan development of the helix 32 issubstantially like an inverted S), whereas the trailing edges arerectilinear. It can be useful to imagine that the helix 32 is obtainedfrom a circle having a given diameter (which is a function of thecylinder diameter), whose two semicircles are shifted along the diameterseparating one from the other in opposite directions until a littleportion keeps them together. The final shape of the helix 32 is obtainedby stamping from the flat configuration shown in FIG. 3a: it can beappreciated from FIG. 5a to FIG. 5d; the stamping has the effect toposition the blade 35 in an inclined plane (see in particular FIG. 5dtogether with FIG. 6a and FIG. 6b), while blade 36 remains in ahorizontal plane. The inclination of the blade 35 with respect to thehorizontal plane containing the blade 36 is of about 15°, so as to meetthe low consumption property required for the bait grinder it is easy tounderstand that during motion the resistance of the blade 35 increasesappreciably with the inclination of this latter (an inclination of 45°must be considered as a maximum value).

The sloping blade 35 of the helix 32 has a triple action: cutting byscything the bait fish fed into the housing 11, driving the thus cuttedchunks of fish and pressing these latter against the pierced disk 33, soas to force such chunks to pass through the holes of the disk; thehorizontal blade 36 has essentially the function of cutting by shearingoff the chunks of fish cutted by scything through the blade 35 andholded back, because of their dimensions, by the holes 33 b of the disk33: the shearing action of the blade 36 is obtained by cooperation withsuch a disk, better said by cooperation with the tailing edges 33 c ofthe holes 33 b, such edges and the blade 36 acting together, during thesliding of this latter on the inner face of the disk 33, as shears (ofcourse, the leading edges 33 d of the holes 33 b, i.e. the edges ofthese latter which the horizontal blade 36 faces first during itsmotion, are not effective from the point of view of the shearing action:in this context, the terms “leading” and “trailing” mean, respectively,“faced first” and “faced last” during motion).

From FIG. 5b to FIG. 5d it is possible to appreciate that the leadingedge 35 a of the sloping blade 35 is sharp on its lower face, whereasthe leading edge 36 a of the horizontal blade 36 is sharp on its upperface (see the numerical references 35 e and 36 e, respectively).

The counter-blade 34 shown in FIG. 3b (see also FIG. 6a and FIG. 6c),which turns together with the double blade helix 32, preserves thefiltering action of the disk 33. It is easy to understand that, in orderto avoid that the counter-blade 34 opposes the action of the two blades35 and 36 of the helix 32, it must be positioned correctly under thedisk 33, preferably under the lower face of the blade 36 and along thetrailing edge 36 b of this latter. The double blade 32 is fastened tothe driven shaft 31 by soldering, whereas the fastening of thecounter-blade 34 to the shaft 31—necessary to drive it together with thehelix 32—is obtained by arranging on the distal end of such a shaft anaxial seat 31 a (see FIG. 6a) on which the counter-blade 34 can bemounted through the complementary hole 34 a shown in FIG. 3b: thecontour of hole 34 a corresponds to that the axial seat 31 a, so it iseasy to understand that such a seat is obtained by bilateral removal,through a cutter, of two opposite portions of the distal end of theshaft 31 in order to give this latter a section in the form of aquadrilateral surface delimited by two opposed rectilinear sides (thelonger ones according to FIG. 3b) and two opposed curved sides (theshorter ones according to FIG. 3b, the curvature being that of shaft31). A spring 70, coaxial with the seat 31 a of the counter-blade 34,retains this latter in contact with the outer face of the disk 33through the upward pressure of a nut 31 b screwed on the thread 31 carranged on the distal end of the shaft 31 before the above mentionedremoval of material; in this manner, the spring 70 exerts an upwardlyoriented axial pressure on the counter-blade 34 and a downwardlyoriented axial pressure on the nut 31 b, and thus on the distal end ofthe shaft 31: this downward pressure ensures the sliding contact betweenthe cutting blade by shearing 36 and the inner face of the disk 33.Furthermore, the spring 70 exerts a useful action on the motor 40 duringthe motion of the driven shaft 31 because of the absorption of theshocks of the sloping blade 35 against the bait fish or chunks of fish.Without such an absorptive action of the spring 70, these shocks wouldswitch the motor 40 off, while lifting upwardly the shaft 31 togetherwith the driving motor 40; on the contrary, because of the presence ofthe spring 70, the upward lifting of the shaft 31 compresses this springwhich exerts the required absorptive action on the shaft 31 and thus onthe motor 40, which can continue turning without stopping. In order tofasten the pierced disk 33 to the housing 11 and thus close the outletof this latter therethrough, it is useful to use a sleeve 50 made ofplastic material (as the motor housing 41 and the fish housing 11 withits mouthpiece 14) which is intended to be put around the lower end ofthe housing 11 (see FIG. 1 and FIG. 2). In the upper half of the sleeve50 are arranged thee buttonholes 51 which are oblong and parallel to itsaxis and set equally apart at 120° one from the next three radialprojections 33 a—they also spaced equally apart (see FIG. 4a)—of thedisk 33 can slide along these buttonholes 51 so as to rest on the closedend thereof; in this position, the disk rests also on a toroidal rib 56(see FIG. 2 in which a portion thereof can be seen in prospect) whichprojects from the inner wall of the sleeve 50. The fastening of thislatter to the housing 11 is obtained by means of three horizontalbuttonholes 52, each one being arranged in the wall of this sleeveperpendicularly to the vertical buttonholes 51 and in communicationtherewith. From the interior of the housing 11 can be introduced threescrews 53, having a special design (see also FIGS. 6a to 6 c), into thebuttonholes 52, of course through three corresponding holes arranged inthe lower portion of the housing 11 and set equally apart at 120° onefrom the next; the head 54 of each screw 53 leans into the cavitydelimited by the housing 11 and has been designed like a little spatuleso as to confer thereto the function of compensating the weightreduction of the column of bait fish inside the housing 11: in fact, asthe quantity of bait fish reduces, the weight of the bait fish above thecutting means 32 reduces too; now, this weight is necessary to exert astopping action on the bait fish immediately above the cutting means 32and thus rendering effective the cutting action thereof; on thecontrary, when the height of the column of bait fish reduces, the weightthereof reduces too, until the height and thus the weight are notsufficient to exert the necessary stopping action on the residual baitfish, which thus escape the action of helix 32. The heads 54 leaninginside the housing 11 are effective to stop the bait fish column abovethe cutting means, especially when the height of this later reduces tothe level of these stopping means 54. The threaded end of the screws 53which protrudes outside the housing 11, from the buttonholes 52, isintended to receive a nut 55 allowing the fastening of the sleeve 50 tothe housing 11. As regards the holes arranged in the disk 33, see FIG.4a and FIG. 4b which show two embodiments given by way of example only.In FIG. 4a a plurality of identical oblong holes 33 b are arrangedcircularly in the peripheric portion of the disk with their axis alignedwith the disk centre, whereas in the central portion of this latter arearranged three holes identical to the former according to the sides ofan equilateral triangle centred around the disk centre. In FIG. 4b thearrangement of the holes in the peripheric portion of the disk is thesame as in FIG. 4a with the difference that the holes are smaller it isthus possible to arrange in the central portion of the disk eightidentical holes according to the sides and the diagonals of a squarecentred around the disk centre. Of course, other arrangements of thedisk holes are possible with holes having the same size or not; anyway,what matters is that the oblong leading and trailing edges 33 d and 33 cof each hole 33 b are never perpendicular to the leading edge of thehorizontal blade 36: this requirement is necessary so as to ensure thatthe blade 36 exerts a shearing action on the chunks of fish retained inthe holes, against the trailing edge 33 c thereof. It can be appreciatedthat the semicircular profile of both the horizontal blade 36 and thesloping blade 35 aims at facing gradually the bait fish to be cutted,thus reducing the motor power and the energetic consumption as well:this can be better appreciated on FIG. 4c, where it is indicated indotted line the angle according to which the semicircular leading edgeof a cutting blade of the helix 32 faces the trailing edge of a diskhole. The oblong character of the housing 11 allows the bait fish columnto exert the above mentioned stopping action on the bait fishimmediately above the helix 32 and to obtain a satisfactory operationrange: with a motor of the type indicated above and a housing having adiameter of 14 cm and a height of 40 cm (corresponding to about 3.5 kgof bait fish) the operation range is of the order of 1.5 hours.

The bait grinder can be equipped with protection means preventingaccidental contacts with the cutting means 30. Such protection meanscomprise a sleeve 60 (see FIG. 1 and FIG. 2), which is coaxial with thesleeve 50 supporting the pierced disk 33 and intended to be putpartially inside this latter sleeve, to which it is fastened by screwand nut means 61. The protection sleeve 60 is intended to support threelittle stems 62 which constitute a sort of protection grate: they arearranged so as to be parallel to each other with their ends inserted incorresponding holes of the sleeve 60, the distance between the stems 62allowing the grinded bait fish to pass therebetween while avoiding theaccidental introduction of the hands of an operator.

On the basis of the above description, it is possible to appreciate thatthe low value of revolutions per minute of the motor shaft, togetherwith the following features, such as: the oblong character of the fishhousing, which ensures the obtention of a fish column above the cuttingmeans having a height sufficient to compensate the low speed of themotor shaft; the arrangement of the cutting means at the lower end ofthe driven shaft and not on the whole length of this latter, the designof the cutting means, which act by scything (thus involvingprogressively a minimum quantity of bait fish) and by shearing (thusinvolving the residual chunks of fish escaped to the means cutting byscything, while ensuring the filtering function from inside the fishhousing); the filtering action of the counterblade outside the fishhousing (during the reduction to practice of the bait grinder accordingto the present invention, it has turned out that without thecounterblade its operation becomes impossible); the progressivecharacter of the cutting ensured by a suitable profile of the leadingedge of the means cutting by scything and by shearing; as well as theshock absorption ensuring a continuous operation of the motor withoutundesirable stopping thereof, contribute individually and in combinationto make the grinder a low consumption device, which is very important inthis field

What is claimed is:
 1. A bait grinder configured for low energyconsumption and for low speed operation, adapted for use in a fishingcraft for cutting bait fish into chum bait and for further grinding thechum bait, comprising: a housing having a substantially vertical axis,an inlet intended for the introduction of the bait fish, and an outletintended for the ejection thereof after reducing the bait fish into chumbait; means for fastening the housing to the craft in a substantiallyvertical position; a vertical shaft having a lower end and an upper endand being intended to occupy a position coincident with the verticalaxis of the housing; means fastened to the shaft for cutting the fishbait; means for driving the shaft; said housing being intended to feedthe bait fish towards the cutting means under the action of gravity,filtering means closing the outlet of the housing; means cooperatingwith the filtering means for keeping the filtering function thereof, andwherein said cutting means are fastened to the lower end of the shaftand comprise: means for cutting by scything the bait fish at the levelof the lower end of the shaft, which scything cutting means are alsomeans for driving and compressing the chum bait so as to grind the chumbait against the filtering means, and means for cutting by shearingresidual chum bait cut by the scything cutting means and retained by thefiltering means, which shearing cutting means are arranged for keeping asliding contact with the filtering means.
 2. The bait grinder as claimedin claim 1, wherein the scything cutting means and the shearing cuttingmeans have a leading edge whose profile allows to face progressively thebait fish to be cut.
 3. The bait grinder as claimed in claim 1, furthercomprising elastic means for forcing the keeping of a sliding contact,on the one hand, between the means for keeping the filtering function ofthe filtering means and the filtering means and, on the other hand,between the filtering means and the shearing cutting means, said elasticmeans further ensuring a shock absorption during the motion of themeans.
 4. The bait grinder as claimed in claim 1, further comprisingmeans for stopping the bait fish immediately above the cutting means asthe quantity thereof decreases during operation.
 5. The bait grinder asclaimed in claim 1, wherein said filtering means comprise a pierced diskin which a plurality of holes are arranged and which is fastened to thehousing; wherein the cutting means comprise a double blade helix;wherein said scything cutting means consist of a first blade of thedouble blade helix which is sloping with respect to the pierced disk,whereas said shearing cutting means consist of a second blade of thedouble blade helix which is horizontal and in sliding contact with aninner face of the pierced disk; wherein said means for keeping thefiltering function of the pierced disk comprise a counter-blade fastenedto the lower end of the shaft and in sliding contact with an outer faceof the pierced disk, and wherein the profile of the sloping andhorizontal blades is semicircular.
 6. The bait grinder as claimed inclaim 5, wherein an axial seat is arranged at the lower end of the shaftwhich is intended to fit a complementary hole arranged in thecounter-blade so as to allow the driving thereof during motion togetherwith the double blade helix, and wherein said forcing and shockabsorption elastic means comprise a spring coaxial with the axial seatof the counter-blade, which spring is kept in contact with thiscounter-blade through a nut threaded around the lower end of the shaft.7. The bait grinder as claimed in claim 5, wherein the pierced disk isfastened to the housing through fastening means consisting of a sleevecoaxial therewith, which is intended to be put around a lower end of thehousing and in an upper portion of which are arranged three verticalbuttonholes set equally apart at 120° one from the next and intended toreceive a corresponding radial projection of the pierced disk.
 8. Thebait grinder as claimed in claim 7, wherein the housing has a toroidalrib projecting from an inner wall thereof and supporting the pierceddisk.
 9. The bait grinder as claimed in claim 8, wherein the upperportion of the coaxial sleeve fastening the pierced disk to the housingcomprises three horizontal buttonholes in communication with thevertical buttonholes supporting the radial projections of the pierceddisk and intended to receive three screws for fastening the coaxialsleeve to the housing, which fastening screws have a head: leaninginside the housing, whereas a threaded end of each fastening screwprotrudes outside the housing so as to receive a fastening nut.
 10. Thebait grinder as claimed in claim 9, wherein said head of the fasteningscrew leaning inside the housing acts as stopping means of the bait fishimmediately above the cutting means.
 11. The bait grinder as claimed inclaim 1, wherein the housing inlet is equipped with a mouthpiece havinga bell-shaped rim facilitating feeding the bait fish into the housingand supporting the driving means, protected by its own motor housing,through a stirrup configured for centering a driving shaft projectingdownwardly from the driving means, and wherein a buttonhole is arrangedin the bell-shaped rim of the mouthpiece so as to avoid rotation of themotor housing while supporting this latter.
 12. The bait grinder asclaimed in claim 1, further comprising means for protection againstaccidental contact with the cutting means, which protection meanscomprise a protection sleeve coaxial with the housing and the fasteningsleeve and intended to be put partially inside this fastening sleeve andto be fastened thereto, the protection sleeve being equipped at a lowerend thereof with a protection grate.